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Who Supplies My Water in the Antelope Valley?
Who supplies my water in the Antelope Valley? Usually the Palmdale Water District, LA County Waterworks District 40, Quartz Hill Water District, Rosamond CSD, Cal Water or a mutual water company; your bill names it.
On this page
Key takeaways
- The Palmdale Water District serves most of Palmdale from the State Water Project, Littlerock Reservoir and 22 wells (2025 report).
- LA County Waterworks District 40 covers Lancaster, Desert View Highlands, Littlerock, Pearblossom, Sun Village, Lake Los Angeles and Rock Creek in separate regional reports.
- AVEK, the Antelope Valley-East Kern Water Agency, is a wholesaler: it treats State Water Project water and sells it to retail suppliers, not to homes.
- Quartz Hill Water District drew about 40% of its 2025 water from 10 wells and the rest from AVEK.
- Rosamond CSD in Kern County blends AVEK water with two of its own wells.
- The State Water Board's service area lookup tool shows which system an address falls in.
This guide is not a water supplier, and it is not affiliated with any agency on this page. Every link below goes to the supplier's own site or report.
Who supplies my water in Lancaster and Palmdale?
In Palmdale, the supplier for most homes is the Palmdale Water District; in Lancaster, it is usually LA County Waterworks District 40. Both cities also contain pockets served by other systems, so the answer for one street can differ from the next. Cal Water runs a small Lancaster system, and some neighborhoods belong to mutual water companies.
Two places beyond the cities have their own districts: Quartz Hill Water District, west of Lancaster, and Rosamond Community Services District, across the county line in Kern County. Behind most of these sits AVEK, which supplies treated State Water Project water to the retailers. The table below lists each one with its latest report.
| Supplier | Areas named in its report | Water sources in the report | Latest report |
|---|---|---|---|
| Palmdale Water District | Most of Palmdale | State Water Project and Littlerock Reservoir via Lake Palmdale (71%), 22 wells (29%) | 2025 CCR, 2025 data |
| LA County Waterworks District 40, Regions 4 and 34 | Lancaster, Desert View Highlands | AVEK surface water (about 53%), District wells (47%) | 2026 report, 2025 data |
| District 40, Regions 24, 27 and 33 | Pearblossom, Littlerock, Sun Village | AVEK Eastside plant (about 65%), wells (35%) | 2026 report, 2025 data |
| District 40, Region 38 | Lake Los Angeles | AVEK (about 69%), wells (31%) | 2026 report |
| Quartz Hill Water District | Quartz Hill | 10 wells (40%), AVEK Quartz Hill plant | 2025 CCR |
| Rosamond CSD | Rosamond, Kern County | AVEK surface water and 2 District wells | 2025 CCR |
| Cal Water, Antelope Valley | Parts of Lancaster, Leona Valley, Lake Hughes, Fremont Valley, Grand Oaks | Wells and AVEK water | 2025 Lancaster CCR |
| AVEK (wholesale only) | Sells to the retail systems above | State Water Project, treated at Acton, Eastside and Quartz Hill plants, plus Water Bank wells | 2025 LA County system report |
What is LA County Waterworks District 40?
LA County Waterworks District 40 is a county-run water district whose reports are published by LA County Public Works, and it is Lancaster's main retail supplier. It is split into regions, each with its own annual report: Regions 4 and 34 for Lancaster and Desert View Highlands, Regions 24, 27 and 33 for Pearblossom, Littlerock and Sun Village, Region 38 for Lake Los Angeles, Region 35 for a single-well area near Lake Los Angeles, and Region 39 for Rock Creek.
The regions draw on different water. Regions 35 and 39 rely entirely on one District well each, while the larger regions blend District wells with AVEK water. All of the regional reports are posted on Public Works' water quality and reports page. For what the Lancaster report shows, see Lancaster water quality.
What does AVEK do?
AVEK, the Antelope Valley-East Kern Water Agency, is the valley's wholesale water agency: it takes State Water Project water from the California Aqueduct, treats it and sells it to retail suppliers. Its 2025 report for the LA County system lists three treatment plants (Acton, Eastside and Quartz Hill) and a Water Bank whose wells store and return water.
AVEK water appears as a column in District 40, Quartz Hill, Rosamond and Cal Water reports, because those systems buy it. A home is billed by its retailer, not by AVEK, so questions about a bill or a pressure problem go to the retailer. AVEK also publishes a separate report for its Kern County system.
Which areas do Quartz Hill and Rosamond serve?
Quartz Hill Water District serves the community of Quartz Hill, and Rosamond Community Services District serves Rosamond in Kern County. Quartz Hill's 2025 report says about 40% of its water came from 10 wells 500 to 600 feet deep, with the rest from AVEK's Quartz Hill plant. Rosamond's 2025 report describes a blend of AVEK surface water and two District wells.
Both districts are dealing with hexavalent chromium (chromium 6). Quartz Hill reported an average of 12 µg/L, above California's 10 µg/L limit, and says it is not in violation of that MCL "until after October 1, 2027", given the system's size. Rosamond's notice of September 2026 states, "Our water system recently violated a drinking water standard," adds that customers do not need an alternative supply such as bottled water, and expects to fix it by October 1, 2027. The hexavalent chromium page explains the limit.
What are mutual water companies?
A mutual water company is a private, not-for-profit water system owned by the people it serves, who hold shares that entitle them to buy its water. A 2024 Assembly committee analysis notes that neither the state's utilities regulator (the PUC) nor the county boundary agencies known as LAFCOs regulate them, apart from limited LAFCO oversight, and that most are small. Those that run a public water system still fall under California's Safe Drinking Water Act.
Several mutual water companies serve parts of Lancaster and the surrounding valley. Each publishes its own annual water quality report, which this guide has not reviewed, so their results are not on this site. If your bill comes from one, ask it for the latest consumer confidence report; every community water system must deliver one by July 1 each year, according to the U.S. EPA.
How do you find your water supplier and its report?
The fastest way to find your water supplier is to read the name on your water bill. If water is included in rent or a homeowners' association fee, ask the landlord or association, or enter the address in the State Water Board's drinking water service area lookup tool, which maps the boundaries of public water systems.
Once you have the name, the supplier's website posts its consumer confidence report, usually under "water quality". California's State Water Board says the 2025 reports, covering January to December 2025, were due to customers by July 1, 2026. Its Drinking Water Watch database also lists each public system. The guide to reading a water quality report explains the tables, and the hardness comparison puts every supplier side by side.
What if your home is on a private well?
If your home is on a private well, nobody publishes a report for it: you are your own supplier, and testing is up to you. In Los Angeles County, the Department of Public Health's drinking water program permits and monitors wells and small water systems; in Kern County, well permits go through Kern County Public Health's Environmental Health Division.
The State Water Board's GAMA program recommends testing a domestic well every year at a lab accredited through the state's ELAP program, and notes that basic sampling can cost $100 to $400. Common tests in this valley include bacteria, nitrate, arsenic and chromium 6. The well water testing guide lists what to ask for.
Antelope Valley suppliers in numbers
- 71%Share of Palmdale Water District's 2025 water from surface sourcesPalmdale Water District 2025 CCR
- 47%Groundwater share for District 40's Lancaster-area regions in 2025LA County Waterworks District 40
- 40%Share of Quartz Hill Water District's 2025 water from its 10 wellsQuartz Hill Water District 2025 CCR
- July 1Annual deadline for community water systems to deliver their consumer confidence reportU.S. EPA
How we put this page together
This directory is built from each supplier's latest report, opened on October 26, 2026: Palmdale Water District (2025 report), the five District 40 regional reports posted by LA County Public Works in June 2026, Quartz Hill Water District, Rosamond CSD (2025 report and September 2026 notice), Cal Water's 2025 Antelope Valley reports and AVEK's 2025 LA County system report, plus the State Water Board's data maps and CCR pages, EPA's CCR page and a 2024 Assembly Local Government Committee analysis. Left out: service area maps drawn by third parties, the names and results of individual mutual water companies (their reports were not reviewed), and supplier phone numbers, which are on each supplier's own site.
Common questions
Does AVEK send me a water bill?
No. AVEK sells treated water wholesale to retail systems, among them Rosamond CSD, Cal Water and District 40, and the retailer is the one that bills the home.
Is Lake Los Angeles water from District 40?
District 40 publishes a report for Region 38, Lake Los Angeles, which says about 69% of its water came from AVEK and 31% from wells. A separate Region 35 report covers a nearby area served by one well.
Who supplies water in Leona Valley?
Cal Water's 2025 report covers a Leona Valley system that blends two wells with AVEK water, which it says helps manage fluoride and nitrate levels.
Where are AVEK's treatment plants?
AVEK's 2025 LA County system report lists three: the Acton, Eastside and Quartz Hill plants. Its Water Bank wells are listed separately, and their results appear as their own column.
Who regulates Antelope Valley water suppliers?
The State Water Board's Division of Drinking Water oversees public water systems in California through its district offices, and each system reports its results in an annual consumer confidence report.
Does the City of Palmdale run the water system?
The reports reviewed here come from the Palmdale Water District, a separate agency with its own board, not from the City of Palmdale. Board meetings are listed in the district's report.
What water system number does Rosamond have?
Rosamond CSD's notices list State Water System Number 1510018, which is how the state identifies the system in its records.
Related guides
More help: see our Antelope Valley home water guide.